On 5 November 2010, a Hawker Beechcraft Corporation B200C aircraft registered VH-MVX departed Dubbo, New South Wales on a positioning flight for a medical charter service from Cobar. Before departure the pilot had set the aircraft altitude on the pressurisation controller for a cabin altitude of 3,000 ft at flight level (FL) of 200. After the aircraft levelled out at FL180 the pilot noticed the cabin altitude was at 10,000 ft instead of 3,000 ft. During a check conducted by the pilot that the cabin pressure control switch was not in the dump position, the aircraft depressurised and the oxygen masks deployed. The pilot did not immediately don his oxygen mask, before initiating an emergency descent and declaring a PAN. The pilot requested clearance to return to Dubbo and landed without further incident about 0745.
The aircraft pressurisation controller was removed and sent to the manufacture for examination. The controller was found to be out of tolerance, a condition that would affect the rate of cabin pressure change responsiveness. As a result of an internal investigation, the operator decided to include a cabin depressurisation exercise requiring an emergency descent as part of their next proficiency check. The operator also will detail the incident and article in their next flight safety newsletter to increase awareness to all pilots.
|Date:||05 November 2010||Investigation status:||Completed|
|Time:||0715 EDT||Investigation level:||Short - click for an explanation of investigation levels|
|Location:||74 Km west of Dubbo|
|State:||New South Wales||Occurrence type:||Air/pressurisation|
|Release date:||16 May 2011||Occurrence class:||Technical|
|Report status:||Final||Occurrence category:||Serious Incident|
|Highest injury level:||None|
|Aircraft manufacturer||Hawker Beechcraft Corporation|
|Type of operation||Aerial Work|
|Damage to aircraft||Nil|